CVE-2022-39957 Response body bypass in OWASP ModSecurity Core Rule Set via a specialy crafted charset in the HTTP Accept header

2022-09-2000:00:00

CWE-693

NCSC.ch

www.cve.org

7.3 High

CVSS3

Attack Vector

NETWORK

Attack Complexity

LOW

Privileges Required

NONE

User Interaction

NONE

Scope

UNCHANGED

Confidentiality Impact

LOW

Integrity Impact

LOW

Availability Impact

LOW

CVSS:3.1/AV:N/AC:L/PR:N/UI:N/S:U/C:L/I:L/A:L

8.7 High

AI Score

Confidence

High

0.002 Low

EPSS

Percentile

64.9%

JSON

The OWASP ModSecurity Core Rule Set (CRS) is affected by a response body bypass. A client can issue an HTTP Accept header field containing an optional “charset” parameter in order to receive the response in an encoded form. Depending on the “charset”, this response can not be decoded by the web application firewall. A restricted resource, access to which would ordinarily be detected, may therefore bypass detection. The legacy CRS versions 3.0.x and 3.1.x are affected, as well as the currently supported versions 3.2.1 and 3.3.2. Integrators and users are advised to upgrade to 3.2.2 and 3.3.3 respectively.

CNA Affected

[
  {
    "vendor": "OWASP",
    "product": "ModSecurity Core Rule Set",
    "versions": [
      {
        "version": "3.0.x",
        "status": "affected"
      },
      {
        "version": "3.1.x",
        "status": "affected"
      },
      {
        "version": "unspecified",
        "lessThanOrEqual": "3.2.1",
        "status": "affected",
        "versionType": "custom"
      },
      {
        "version": "unspecified",
        "lessThanOrEqual": "3.3.2",
        "status": "affected",
        "versionType": "custom"
      }
    ]
  }
]